Ultrasonic endoscope

The present application claims priority under 35 U.S.C § 119(a) to Japanese Patent Application No. 2022-152751 filed on Sep. 26, 2022, which is hereby expressly incorporated by reference, in its entirety, into the present application.

The present invention relates to an ultrasonic endoscope, and in particular, to an ultrasonic endoscope provided with a radial type ultrasound transducer in a distal end part of an insertion part.

In recent years, an ultrasonic endoscope is used in a medical field. The ultrasonic endoscope comprises an ultrasound transducer that irradiates an inside of a body of a subject with an ultrasonic wave and that receives and images a reflected wave of the ultrasonic wave. As such an ultrasonic endoscope, an ultrasonic endoscope provided with a radial type ultrasound transducer in a distal end part of an insertion part is disclosed in JP2022-124502A. With the ultrasonic endoscope, the ultrasound transducer and an ultrasonic cable are electrically connected inside the insertion part.

The ultrasonic endoscope of JP2022-124502A has a pressing member that supports a distal end-side portion of the ultrasonic cable. The pressing member is provided on a proximal end side of the ultrasound transducer.

The ultrasonic endoscope has a plurality of contents, such as a light guide fiber, a forceps channel, and an air/water supply channel, as contents inserted into the insertion part, in addition to the above-described ultrasonic cable.

To achieve a reduction in diameter of the insertion part, in a case of determining a disposition position of each content inserted into the insertion part, there is a case where the position of the forceps channel having the greatest outer diameter among the contents is first determined, and thereafter, the positions for disposing the contents, such as the ultrasonic cable and the light guide fiber, in a remaining free space are determined.

By the way, because an internal space of the insertion part is extremely narrow, the contents may interfere with each other inside the insertion part. In this case, one content of the contents interfering with each other should be disposed to be offset (shifted) from the other content. As a configuration (hereinafter, referred to as an offset configuration) in which the contents are offset, for example, a configuration is considered in which, in a case where the light guide fiber and the ultrasonic cable interferes with each other, a part of the light guide fiber is made to abut on a distal end of a pressing member (hereinafter, referred to as a bracket) disclosed in JP2022-124502A to offset the light guide fiber.

Note that, in a case where the offset configuration is employed, because a part of the light guide fiber is made to rub on the distal end of the bracket, the light guide fiber may be damaged.

The present invention has been accomplished in view of such a situation, and an object of the present invention is to provide an ultrasonic endoscope capable of solving a damage problem of the light guide fiber due to the bracket.

To attain the above-described object, there is provided an ultrasonic endoscope according to an aspect of the present invention comprising a radial type ultrasound transducer that is provided in a distal end part of an elongated insertion part to be inserted into a subject, an illumination window that is provided in a distal end surface of the distal end part, a light guide fiber that is inserted into the insertion part and guides illumination light to the illumination window, an ultrasonic cable that is inserted into the insertion part and is connected to the ultrasound transducer, and a bracket that is disposed inside the insertion part and has a bracket body portion that supports a distal end-side portion of the ultrasonic cable, in which, in a case of being projected on a plane perpendicular to a longitudinal axis direction of the insertion part, the distal end-side portion of the ultrasonic cable or the bracket body portion is disposed at a position overlapping or adjacent to at least a part of a distal end-side portion of the light guide fiber, and a pressing portion that is disposed inside the insertion part, has a pressing surface against which a pressed portion as a part of the light guide fiber is pressed, and is configured in such a manner that a body portion disposed on a proximal end side with respect to the distal end-side portion of the light guide fiber is disposed at a position away from the bracket body portion in a direction perpendicular to the longitudinal axis direction by pressing the pressed portion against the pressing surface is provided.

According to an aspect of the present invention, it is preferable that, in a case of being projected on the plane perpendicular to the longitudinal axis direction, the distal end-side portion of the light guide fiber and the distal end-side portion of the ultrasonic cable are disposed at a position at least partially overlapping each other.

According to an aspect of the present invention, it is preferable that the ultrasonic endoscope further comprises a cylindrical base member that has an outer peripheral surface and an inner peripheral surface, and supports the ultrasound transducer on the outer peripheral surface, in which the base member has the pressing portion on the inner peripheral surface.

According to an aspect of the present invention, it is preferable that the pressing surface has a tapered shape inclined with respect to the longitudinal axis direction.

According to an aspect of the present invention, it is preferable that the bracket has the pressing portion.

According to an aspect of the present invention, it is preferable that the pressing portion is a protruding portion that protrudes from a distal end side of the bracket body portion, and the protruding portion has a bent or flexed shape in a direction separate from the bracket body portion.

According to an aspect of the present invention, it is preferable that the pressing surface has an R-shaped surface convex toward the pressed portion of the light guide fiber.

According to an aspect of the present invention, it is preferable that the pressing portion is disposed inside the distal end part of the insertion part.

According to the present invention, it is possible to solve a damage problem of a light guide fiber due to a bracket.

Hereinafter, an embodiment of an ultrasonic endoscope according to the present invention will be described referring to the accompanying drawings.

is a schematic configuration diagram showing an example of an ultrasonography systemthat uses an ultrasonic endoscopeof the embodiment.is an enlarged perspective view showing an appearance of a distal end part of the ultrasonic endoscopeshown in.

Ultrasonography System

As shown in, the ultrasonography systemcomprises the ultrasonic endoscope, an ultrasound processor devicethat generates an ultrasound image, an endoscope processor devicethat generates an endoscope image, a light source devicethat supplies illumination light, with which the inside of a body cavity is illuminated, to the ultrasonic endoscope, and a monitorthat displays the ultrasound image and the endoscope image. The ultrasonography systemcomprises a water supply tankthat stores cleaning water or the like, and a suction pumpthat sucks aspirates inside the body cavity.

The ultrasound processor devicegenerates and supplies an ultrasound signal for making the ultrasonic observation partof the ultrasonic endoscopegenerate an ultrasonic wave. The ultrasound processor devicereceives and acquires an echo signal reflected from an observation target part irradiated with the ultrasonic wave, by the ultrasonic observation partand executes various kinds of signal processing on the acquired echo signal to generate an ultrasound image.

The endoscope processor devicereceives an image signal acquired from the observation target part illuminated with the illumination light from the light source devicein the endoscope observation partof the ultrasonic endoscope. Then, the endoscope processor deviceexecutes various kinds of signal processing and image processing on the acquired image signal to generate an endoscope image.

In the present example, the ultrasound processor deviceand the endoscope processor deviceare configured with two devices (computers) provided separately. Note that the present invention is not limited thereto, and both the ultrasound processor deviceand the endoscope processor devicemay be configured with one device.

The light source devicegenerates illumination light, such as white light consisting of light of three primary colors of red light, green light, and blue light or light of a specific wavelength. The illumination light propagates through the ultrasonic endoscopeand is emitted from the endoscope observation part, and the observation target part inside the body cavity is illuminated with the illumination light.

The monitorreceives respective video signals generated by the ultrasound processor deviceand the endoscope processor deviceand displays an ultrasound image and an endoscope image. In regard to the display of the ultrasound image and the endoscope image, only one image may be appropriately switched and displayed on the monitoror both images may be displayed simultaneously.

In the present example, although the ultrasound image and the endoscope image are displayed on one monitor, a monitor for ultrasound image display and a monitor for endoscope image display may be provided separately. Alternatively, the ultrasound image and the endoscope image may be displayed in a display form other than the monitor, for example, in a form of being displayed on a display of a terminal carried with an operator.

Ultrasonic Endoscope

As shown in, the ultrasonic endoscopehas an elongated insertion partthat is inserted into the subject, an operating partthat is consecutively provided in a proximal end part of the insertion partand is used by the operator to perform an operation, and a universal cordthat has one end connected to the operating part.

In the operating part, an air/water supply buttonthat opens and closes an air/water supply pipe line (not shown) from the water supply tank, and a suction buttonthat opens and closes a suction pipe line (not shown) from the suction pumpare provided side by side. In the operating part, a pair of angle knobsand a treatment tool insertion portare provided.

In the other end portion of the universal cord, an ultrasound connectorthat is connected to the ultrasound processor device, an endoscope connectorthat is connected to the endoscope processor device, and a light source connectorthat is connected to the light source deviceare provided. The ultrasonic endoscopeis attachably and detachably connected to the ultrasound processor device, the endoscope processor device, and the light source devicethrough the connectors,, and, respectively. The connectoris provided with an air/water supply tubethat is connected to the water supply tank, and a suction tubethat is connected to the suction pump

The insertion parthas, in order from a distal end side, a distal end hard part(see) that has an endoscope observation partand an ultrasonic observation part, a bendable partthat is connected to a proximal end side of the distal end hard part, and a soft partthat connects a proximal end side of the bendable partand a distal end side of the operating part. The distal end hard part, the bendable part, and the soft partare provided along a longitudinal axis A direction of the insertion part. The bendable partis made by connecting a plurality of bending pieces(see) and is configured to be freely bent. The soft partis slender and long, and has flexibility.

The bendable partis remotely bent and operated by rotationally moving and operating a pair of angle knobsprovided in the operating part. With this, the distal end hard partcan be directed in a desired direction.

is a sectional view of the distal end hard part.shows a plurality of bending piecesconfiguring the bendable part, and a plurality of (in, two) bending operating wiresof which a distal end side is connected to the bendable partand a proximal end side is connected to a pair of angle knobs(see).

Next, the configuration of the distal end hard partand a plurality of contents that are inserted into the insertion partwill be described referring to. As shown in, the distal end hard partis provided with the endoscope observation partthat acquires the endoscope image, on the distal end side, and the radial type ultrasonic observation partthat acquires the ultrasound image, on the proximal end side. The distal end hard partis an example of a distal end part of an insertion part of the present invention.

The distal end hard parthas a cap-shaped distal end componentthat covers a distal end-side portion of the endoscope observation part, and a proximal end-side ring (also referred to as a balloon ring)that is disposed on a proximal end side of the ultrasonic observation part. The distal end componentand the proximal end-side ringare made of an insulating member, such as hard resin, and serve as an exterior member.

As shown in, a cylindrical base member(also referred to as a shield ring) is connected to a proximal end side of the distal end component. The ultrasound transducerthat configures the ultrasonic observation partis disposed on an outer peripheral surface of the base member. The base memberhas a function of shielding electromagnetic waves emitted from the ultrasound oscillatorsof the ultrasound transducer, in addition to a function of supporting the ultrasound transducer. Light guide fibersare disposed inside the base member.

Returning to, the endoscope observation partincludes a treatment tool outlet portthat is opened on a distal end surfaceof the distal end component, observation window, illumination windows, a cleaning nozzle, and the like. Two illumination windowsare provided with the observation windowinterposed therebetween.

A distal end side of a forceps channel (not shown) is connected to the treatment tool outlet port. The forceps channel is inserted into the insertion partshown in, and a proximal end side of the forceps channel is connected to the treatment tool insertion portof the operating part. A treatment tool, such as forceps, is inserted into the forceps channel from the treatment tool insertion portand is led out from the treatment tool outlet portof. With this, treatment of the subject is performed by the treatment tool. The above-described forceps channel is one of a plurality of contents that are inserted into the insertion part.

An observation system unit (not shown) is connected to the observation windowshown in. The observation system unit includes an objective lens, a prism, an imaging element, a substrate, cables, and the like.

Reflected light of the observation target part incident from the observation windowis taken in by the objective lens. An optical path of the taken-in reflected light is folded at a right angle by the prism, and the reflected light forms an image on an imaging surface of the imaging element. The imaging element photoelectrically converts the reflected light of the observation target part that has formed the image on the above-described imaging surface to output an image signal. Examples of the imaging element include a charge coupled device (CCD) and a complementary metal oxide semiconductor (CMOS).

The imaging element is mounted on the substrate. A circuit pattern that is electrically connected to the imaging element is formed on the substrate. The circuit pattern comprises a plurality of electrodes in an end portion, and a plurality of signal lines are connected to a plurality of electrodes, respectively. The signal lines are inserted into the operating partfrom the bendable partthrough the soft partshown inin a state of a shield cable including a plurality of signal lines. Then, a plurality of signal lines are inserted into the universal cordfrom the operating partand are connected to the endoscope connector. The endoscope connectoris connected to the endoscope processor device. The above-described shield cable is one of a plurality of contents that are inserted into the insertion part.

A distal end (emission end)of the light guide fibershown inis connected to the illumination windowshown in. The light guide fiberof the present example includes a fiber body, a tubewith which the fiber bodyis coated, and a connecting pipethat is connected to a distal end of the tube, and a distal endA of the connecting pipeis connected to the illumination window. The light guide fiberextends from the insertion partto the operating partshown inand is inserted into the universal cordfrom the operating part, and a proximal end (incidence end) of the light guide fiberis connected to the light source connector. The light source connectoris connected to the light source device. Illumination light emitted from the light source devicepropagates through the light guide fiber, and a part to be observed is irradiated with the illumination light from the illumination windowof. Two light guide fibersare provided corresponding to the two illumination windowsand. The above-described light guide fiberis one of a plurality of contents that are inserted into the insertion part, and is an example of a light guide fiber of the present invention.

A distal end of an air/water supply channel (not shown) is connected to the cleaning nozzleshown in the distal end of. The air/water supply channel extends from the insertion partto the operating partshown inand is inserted into the universal cordfrom the operating part. Then, a proximal end of the air/water supply channel is connected to the light source connectorand is connected to the water supply tankthrough the air/water supply tube. To clean the surfaces of the observation windowand the illumination windows, the cleaning nozzlejets air or cleaning water supplied from the water supply tankby way of the air/water supply channel toward the observation windowand the illumination windows. The above-described air/water supply channel is one of a plurality of contents that are inserted into the insertion part.

The ultrasonic observation partshown inis configured with the ultrasound transducer. The ultrasound transduceris configured as a radial type ultrasound transducer, and is configured by arranging a plurality of ultrasound oscillatorsin a peripheral direction of the outer peripheral surface of the base membershown in.

As shown in, the ultrasound transduceris an array of a plurality of channels (CH) made of a plurality of ultrasound oscillators, for example, 48 to 192 rectangular parallelepiped ultrasound oscillatorsarranged in a cylindrical shape. In the ultrasound transducer, as an example, a plurality of ultrasound oscillatorsare arranged at predetermined pitches in a peripheral direction as in the example shown in the drawing. In this way, the ultrasound oscillatorsconstituting the ultrasound transducerare arranged at regular intervals on the periphery around a central axis (the longitudinal axis A of the insertion part) of the distal end hard part. The respective ultrasound oscillatorsare sequentially driven based on a drive signal input from the ultrasound processor device(see). Thus, radial electronic scanning is performed with a range in which the ultrasound oscillatorsare arranged, as a scanning range.

As shown in, the ultrasound transducerincludes an electrode partthat comprises a plurality of individual electrodescorresponding to a plurality of ultrasound oscillatorsand a common electrodecommon to a plurality of ultrasound oscillators, a flexible print substrateto which each of a plurality of individual electrodesis connected, and the base memberthat supports a plurality of ultrasound oscillatorson the outer peripheral surface.

The ultrasound transducerhas an acoustic matching layerlaminated on an outer peripheral surface side of the ultrasound oscillators, an acoustic lenslaminated on an outer peripheral surface side of the acoustic matching layer, and a backing material layerlaminated on an inner peripheral surface side of the ultrasound oscillators. The ultrasound transduceris made of a laminate of the acoustic lens, the acoustic matching layer, the ultrasound oscillators, and the backing material layer. The laminate is supported on the outer peripheral surface of the base memberby a method, such as fitting.

The acoustic matching layeris provided for taking acoustic impedance matching between the subject, such as a human body, and the ultrasound oscillators.